Adjustable muffler



July 2l, 1964 E. w. BOTTUM ADJUSTABLE MUFFLER 2 Sheets-Sheet 1 Filed Sept. l0, 1962 f 1% m f v um \Z im@ Z /ls a Q( f m Z w r 6 1n mm mr T ww uw WM J r o R M an U y fw w M July 21, 1964 E. w. BoTTuM 3,141,519

ADJUSTABLE MUFFLER Filed Sept. l0, 1962 2 Sheets-Sheet 2 INVENTOR.

JA/:50M SETTLE a Clan/G ,4free/Veni United States Patent O 3,141,519 ADJUSTABLE MUFFLER Edward W. Bottum, 9357 Spencer, Brighton, Mich. Filed Sept. 10, 1962, Ser. No. 222,411 '7 Claims. (Cl. 181-57) The present invention relates to an adjustable muiiier, and more particularly to a muiiier for use in reducing pulsations and noise in systems in which air or other gas iiows, the muier being adjustable to be effective in diiferent systems. f

The muier of the present invention may be used in any system in which a gas must be exhausted, such as from the operation of a gasoline or other engine or in connection with the compressor of a refrigeration system. The muiiier may be used on either the suction or discharge side of a compressor or engine. However, the greatest effect from the muliier is normally achieved by installing it in the discharge line of a compressor or the exhaust line of an engine. The muiiler is particularly useful in refrigeration systems where the elimination of noise is highly important.

The use of muiiiers has, of course, been quite common in the past. However, the use of conventional prior art muiiiers has to some extent been unsatisfactory in systems where high quality muffler performance is necessary. The configuration of the muiiier is very important with reference to the performance of the mutiier. The pressure drop and orifice conditions in the muiiier can significantly affect muflier performance. Muiiier performance is particularly important in refrigeration systems where the pressure drop through the muliier and the amount of noise suppression in the muliier are very important. A muffler may perform satisfactorily with one refrigeration compressor at a given suction pressure or load condition. However, if the operating conditions of the compressor are changed, or if the muiiier is utilized in a different system, resulting in a different pressure drop through the muliier, the performance of the muliier may be quite unsatisfactory.

It is, therefore, an object of the invention to provide an adjustable muffler.

Another object of the invention is to provide a muiiler which, when installed in a system, may be adjusted to vary the orifice opening Within the mutiier with a consequent variation to the resistance to liow in the muffler.

A further object of the invention is to provide a muffler having a plurality of bafies with orifice openings which are adjustable externally of the muier without the escape of gas from the system.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawing forming a part of this speciication wherein like reference characters designate corresponding parts in the several views.

In the drawing:

FIGURE l is a side elevational view in section of one embodiment of an adjustable muffler according to the present invention;

FIGURE 2 is a side elevational view in section of another embodiment of the invention;

FIGURE 3 is a side elevational view in section of still another embodiment of the invention;

FIGURE 4 is a side elevational view in section of a further embodiment of the invention; and

FIGURE 5 is a partial sectional view of the FIGURE 4 embodiment showing the muiiier in an adjusted position.

Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawing,

ldll@ Patented July 21, 1964 since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

Referring to FIGURE l, it will be seen that the mufiier 1GB comprises a casing including a hollow cylindrical member I2 having end closures I4, 16 secured thereto. The closures i4, 16 may be secured to the member 12, as may be other components of the muffler, by any suit able method such as brazing.

The closures 14, i6 have openings 13, 20 in which are secured, respectively, inlet fitting 22 and outlet iitting 24. The inlet and outlet are suitable attached to conduits (not shown) in the system in which the muiier is used.

Secured within the member 12 are a plurality of spaced apart cup-shaped baille plates 26. Each baffle plate 26 is provided with a small opening 23 adjacent the lower portion of member I2 for the flow of oil through the mutlier. Oil is, of course, present in the gases of a refrigeration system.

A relatively large opening itil is provided centrally of each plate 26. The openings 3d are provided for the flow of gas through the muffler.

Extending axially through the openings Sil is a shaft 32. The shaft 32 carries a plurality of spaced apart closure members 34, one for each plate .26 and positioned adjacent each opening Sil. T he closure members 34 are provided to permit variation of the orifices formed by openings Sil of the plates 26 and adjacent closiu'es 34.

The shaft 32 to which the closure members are secured is axially adjustable to permit varying the distance of the closure members from the baiiie plate 26. As will be noted, the inner end of the shaft is slidably received through an opening 36 in a guide member 38 which is secured to the end closure I4. A support and sealing member 40 is provided at the opposite end of the muiiier. The member 46 is received in an opening 42 of the end closure 16 and is secured thereto. The member 40 has an internally threaded axial opening 44 therethrough. The shaft 32 has a threaded portion 46 which is threadingly received in the opening 44. As will be noted, a portion of the shaft extends exteriorly of the muliier and has a wrench engageable head 43 for threading the shaft in the member 40. A packing gland 5l) is provided to seal the opening 44 against escape of gas from within the muier. The gland 50 is conventional in structure, comprising a nut 52 which is threadingly received in threaded portion 53 of opening 44. An annular sealing element 54, fabricated from asbestos-graphite or the like, is positioned within opening 44 and is wedged into sealing engagement with the shaft 32 and angular wall portion 56 by the nut 52.

An internally threaded cap 5S is received on external threads 60 of the member 49. The cap 5S serves to further seal the muffler so that any gas which does escape by the sealing element 54 is further restricted from escaping from the system. The cap 58 is, of course, removed when it is desired to adjust the shaft 32.

In operation of the muffler lil, the muffler is installed in a system by attachment of suitable conduits to the inlet and outlet 22, 24. The cap 58 is then removed, and the shaft 32 is threaded into or out of the member 4l] to move the closure elements 34 closer to or further from the plates 26. This adjustment varies the size of the oriices through the plates 26. The extent of the adjustment, which is made while the system is in operation, is determined by the noise level of the muiiler. That is, the shaft 32 is adjusted axially to achieve the lowest possible noise level.

Variation in the size of the orifice openings varies the resistance to the ilow of gas. This is of importance in muiller performance. Additionally, changing the position of the closures will vary the deflection of the gas and change the turbulence characteristics of the gas which are also important factors in muiller performance.

An alternate construction is illustrated in FIGURE 2. In the FIGURE 2 construction, a separate internal guide and support member for the shaft 62, such as the member 38, is not used. Instead, the shaft 62 extends through an opening 64 provided in the rst bale plate do. The baille plate 66 has an opening dit adjacent to the lower portion of the casing 7l). rIhe opening 6% serves as a path for both the oil and gas which enter the muiller. The remaining baille plates '72, 711 are substantially identical to the baille plates Z6 provided in the FIGURE 1 construction. The shaft 62 is provided with closure elements 76, 78 which act to vary the orifices through the openings 80, 81?. in the plates '72, '74 as previously described. The shaft 62 is axially adjustable in the same manner as the shaft 332 of the FIGURE 1 embodiment.

Another construction is illustrated in FIGURE 3. In the FIGURE 3 construction, a tube 8d extends through openings 86 in baille plates SS. The tube 34 has a plurality of peripherally spaced openings 9@ at the juncture of each baille plate d8. The openings 90 serve as a path for gas by the baille plates i.

The size of the oriilce through the openings 9i) is made adjustable by the provision of a rod 92 which slidingly extends into the tube 842-. As will be noted, the rod 92 has a portion 9d of reduced diameter adjacent each of the openings 9d. The rod 92 has a threaded portion 96 of reduced diameter which is threadingly engaged in member 9S. The structure of member 98 is identical with the member d@ of the FIGURE l embodiment.

As will be appreciated, the rod 92 may be moved axially within the tube 84.1 by threading the reduced portion 96 thereof into or out of the member 98. Axial movement of the rod 92 in either direction will act to reduce the oriilce created by the openings Sil and the portions 94 of reduced diameter of the rod 92. Thus, the muiller of FIGURE 3 is adjustable in a manner similar to the FIGURE 1 embodiment.

The muiller structure illustrated in the various figures may be modified as desired to suit particular conditions. For example, only the ilrst or second baille plates nearest the outlet or inlet may be made adjustable. Additionally, the closures on the adjustable shaft may be in any shape or conilguration to provide desired muiller characteristics.

Once the muiller of the present invention is installed, it may be quickly adjusted to the system to provide best performance. This eliminates the time and expense involved in installing different mutllers to achieve top performance. Additionally, an adjustable mufer provides an almost inilnite range of adjustment which is not possible by using diilerent muillers.

FIGURE 4 illustrates a further modification of the muiller, In this embodiment, baille plates lill? form compartments 102 within the casing ldd. A tube 106 extends through openings 168 in the bales. Gas llows into tube 1% from inlet compartment 111@ and ilows therefrom into outlet compartment 112. Annularly spaced openings 114 are provided in tube 1de in each compartment 162. The openings 11d permit the flow of gas into and out of the compartments 162 as the pressure of the input gas in the tube 1695 varies to thus accomplish the muffiing function. A second tube 116 is rotatably mounted within the tube 106. The tube 11d is manually rotated to different positions within tube 1% by actuation of a shaft 1W which is connected to the tube by a spider 109 and extends through a gas-tight fitting 111 to terminate exteriorly of the casing. Tube 11o is provided with annularly spaced openings 11S which are in annular alignment with the openings 114. As will be appreciated, the tube 116 may be rotated to diilerent positions as shown in i FIGURE 5 wherein the openings 114, 118 are not in exact registry to thereby vary the size of the orifices formed by the openings and thus alter the muiller characteristics to suit different circumstances.

Having thus described my invention, I claim:

l. An adjustable muiller comprising a casing having an inlet and an outlet, a plurality of spaced apart bailles in the casing, said bailles having openings therethrough for the passage of gas through the muiller, a shaft extending into the casing from the exterior thereof, sealing means between the shaft and casing forming a gas-tight seal, a cap over the external portion of the shaft to effect an additional gas-tight seal, said shaft having means providing at least one closure element adjacent one of the openings of a baffle, said closure being related to the opening of the adjacent baille to form an orifice through the baffle, said shaft being axially movable by actuation thereof exteriorly of the casing to adjust the position of the closure to thereby adjust the size of said orifice.

2. A device as claimed in claim l and further characterized in that a closure element is provided on the shaft for each baffle, axial movement of the shaft being eifective to adjust the orifice formed by each baille opening and related closure element.

3. An adjustable muiller comprising a casing having an inlet and an outlet, a plurality of spaced apart bailles in the casing, said bailles having registering openings therethrough for the passage of gas through the mufller, said casing having an opening therein, a shaft extending from a point exteriorly of the casing through said casing opening and through the baille openings, sealing means on the casing opening to etlect a gas-tight seal, a cap over the external portion of the shaft to eilect an additional gas-tight seal, a plurality of spaced apart closure elements provided on the shaft, each of said closure elements being adjacent one of the baille openings, each of said closures being related to the opening of its respective adjacent baille to form an oriiice through the baille, said shaft being axially movable by actuation thereof externally of the casing to adjust the relative position of the closures and adjacent bailles to thereby adjust the size of the said orices.

4. A device as claimed in claim 3 and further characterized in the provision of a guide element within the casing, said guide element having an opening therein, the end of the shaft within the casing being slidably received in the opening of the guide element.

5. A device as claimed in claim 3 and further characterized in that said casing opening is internally threaded, a threaded portion on said shaft threadingly engaging said opening whereby rotation of the shaft is effective to thread the shaft into or out of the casing.

6. An adjustable muiller comprising a casing having an inlet and an outlet, a plurality of spaced apart bailles in the casing, one of said bailles having a relatively small opening and a relatively large opening, the remainder of said baffles having relatively large openings in registry with the relatively small opening of said one baille, said relatively large openings being provided for the passage of gas through the muffler, said casing having an opening, a shaft extending externally of the casing through said casing opening and through said relatively large registering openings and slidably received in said relatively small opening of said one baille, sealing means on the casing opening to effect a gas-tight seal, a cap over the external portion of the shaft to eifect an additional gas-tight seal, a plurality of closure elements provided on the shaft, each of said closure elements being positioned adjacent one of said relatively large registering baille openings, said closure elements being related to the respective openings of the adjacent bailles to form oriilces through the bailles, said shaft being movable by actuation thereof externally of the casing to adjust the relative position of the closure elements and adjacent bailles to thereby adjust the size of said orices.

7. An adjustable muiiier comprising a casing having an inlet and an outlet, a plurality of spaced apart baies in the casing, said baffles having registering openings therethrough, a tube received in said registering openings, said tube having openings at the juncture of the tube with each battle for the passage of gas through the mutlier, a rod slidably received in the tube, said rod having a portion of reduced diameter adjacent each of the tube openings, said rod being movable in the tube, an opening in the casing, said rod having a portion extending through said casing opening and terminating externally of the casing, sealing means on the casing opening to effect a gas-tight seal, a cap over the external portion of the rod to effect an additional gas-tight seal, said rod being movable in the tube by actuation of the portion of the rod external of the casing, movement of the rod being eifective to adjust the position of the portions of the rod of reduced diameter with respect to the tube openings to thereby adjust the size of the orices formed by said tube openings and said portions of the rod of reduced diameter.

References Cited in the tile of this patent UNITED STATES PATENTS 1,153,097 Miller Sept. 7, 1915 1,173,583 Johnston Feb. 29, 1916 1,291,271 Tvedt Ian. 14, 1919 1,354,834 Martel Oct. 5, 1920 1,567,298 Reinhardt Dec. 29, 1925 2,382,159 Klemm Aug. 14, 1945 

1. AN ADJUSTABLE MUFFLER COMPRISING A CASING HAVING AN INLET AND AN OUTLET, A PLURALITY OF SPACED APART BAFFLES IN THE CASING, SAID BAFFLES HAVING OPENINGS THERETHROUGH FOR THE PASSAGE OF GAS THROUGH THE MUFFLER, A SHAFT EXTENDING INTO THE CASING FROM THE EXTERIOR THEREOF, SEALING MEANS BETWEEN THE SHAFT AND CASING FORMING A GAS-TIGHT SEAL, A CAP OVER THE EXTERNAL PORTION OF THE SHAFT TO EFFECT AN ADDITIONAL GAS-TIGHT SEAL, SAID SHAFT HAVING MEANS PROVIDING AT LEAST ONE CLOSURE ELEMENT ADJACENT ONE OF THE OPENING OF A BAFFLE, SAID CLOSURE BEING RELATED TO THE OPENING OF THE ADJACENT BAFFLE TO FORM AN ORIFICE THROUGH THE BAFFLE, SAID SHAFT BEING AXIALLY MOVABLE BY ACTUATION THEREOF EXTERIORLY OF THE CASING TO ADJUST THE POSITION OF THE CLOSURE TO THEREBY ADJUST THE SIZE OF SAID ORIFICE. 